Blar i utgivelsesdato Doktorgradsavhandlinger (BFE-fak)

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    • Quantification and characterisation of residual blood in fish muscle : impact of slaughtering methods 

      Olsen, Stein Harris (Doctoral thesis; Doktorgradsavhandling, 2011-06-17)
      Omorganisering i oppdrettsnæringen har ført til større og mer mekaniserte anlegg med høy slaktekapasitet. I dag kontrolleres normalt restblod i fiskefilet ved visuell inspeksjon. Dette er arbeidskrevende og innebærer subjektive evalueringer som muliggjør høy grad av unøyaktighet. Fargen på fiskemuskelen er også et viktig kriterium når kunder vurderer kvalitet, og disse fargeforandringene skyldes ...

    • Staying alive : the survival and importance of Atlantic salmon post-spawners 

      Halttunen, Elina (Doctoral thesis; Doktorgradsavhandling, 2011-08-19)
      Summary Atlantic salmon (Salmo salar L.) repeat-spawners might play an important role in population persistence by increasing both total recruitment and long-term stability of a population. This is because repeat spawners return at larger sizes and with greater fecundity than first time spawners, and the large majority of repeat-spawners are females. Nevertheless, little knowledge exists of this ...

    • Poverty in Small-Scale Fisheries : Governance Challenges in Lake Victoria Fishing Communities, Tanzania 

      Onyango, Paul Ochieng (Doctoral thesis; Doktorgradsavhandling, 2011-08-23)
      The pursuit of a world without poverty is without doubt among the leading global challenges not only for governments but also the poor themselves. This challenge is also in small-scale fishing communities where poverty is persistent and has become a thorny issue to the poor as well as governing actors. Strategies have been formulated and implemented but the results have not been up to the expectations. ...

    • Granularity and its importance for traceability in seafood supply chains 

      Karlsen, Kine Mari (Doctoral thesis; Doktorgradsavhandling, 2011-08-26)
      The purpose of this thesis was to study granularity and its importance for traceability in seafood supply chains. The following hypothesis was applied in this thesis: The implementation of traceability of seafood is affected by the granularity level of the traceable units. Three sub-tasks were carried out to test the hypothesis: 1) identify critical traceability points (CTPs) of seafood products, ...

    • Bacterial flagellin : a novel adjuvant for vaccine strategies 

      Hynes, Natasha (Doctoral thesis; Doktorgradsavhandling, 2011-10-18)
      Flagellin is the principal structural protein in the locomotive organ flagellum present on flagellated bacteria, and is known to be an important evolutionarily conserved PAMP. Flagellin has been shown to bind to the PRR TLR5 which induces innate immune system responses and signaling pathways. In mammals, much focus has been placed on this protein in vaccine studies for its possible function as an ...

    • Species concepts and functional aspects of cold-water diatoms (Bacillariophyceae) 

      Degerlund, Maria (Doctoral thesis; Doktorgradsavhandling, 2011-10-18)
      The choice of species concept when delineating phytoplankton species is decisive for our knowledge of species diversity and distribution, but will also affect our understanding of the functioning of marine ecosystems. This is particularly true for so-called cryptic species, which may show high degree of genetic and physiological heterogeneity although being morphologically similar. A precise species ...

    • Acute and long-term effects from petroleum discharges on temperate and Arctic Calanus species 

      Jensen, Louise Kiel (Doctoral thesis; Doktorgradsavhandling, 2011-11-11)
      Summary Petroleum exploitation is emerging in the Arctic. In the Norwegian Arctic the southern Barents Sea is opened for development of oil and gas fields. This same area holds some of the world's largest and well managed commercial fish stocks such as Herring (Clupea harengus), Capelin (Mallotus villosus), Haddock (Melanogrammus aeglefinus), Atlantic Cod (Gadus morhua). For the interest of the ...

    • Cellular responses induced by environmental stress factors in Arctic Seabird chicks : Responses of the antioxidant defense system and autophagic lysosomal processes related to contaminant exposure and food restriction 

      Hegseth, Marit Nøst (Doctoral thesis; Doktorgradsavhandling, 2011-11-29)
      This PhD study has investigated how two commonly occurring environmental stress factors in the Arctic (periods with little food and exposure to halogenated organic contaminants) have had an impact on two important cellular defense mechanisms in Arctic seabirds. The antioxidant defense system and autophagic lysosomal responses in liver cells of Arctic seabird chicks have been studied. Samples ...

    • Primary production and the relevance of small autotrophic and heterotrophic cells in marine arctic ecosystems 

      Hodal, Helene (Doctoral thesis; Doktorgradsavhandling, 2011-12-02)
      The Arctic is one of the least studied regions in the world and large changes in marine ecosystem dynamic are expected here because of the increasing air and ocean temperature. The central Arctic Ocean has for a long time been considered as a very low productive ecosystem, but recent estimates of primary production gives relatively high values. The shelves surrounding the Arctic Ocean are highly ...

    • Planktonic food webs in the Arctic Ocean : structure and function in contrasting seasons and physical settings across Fram Strait 

      Seuthe, Lena (Doctoral thesis; Doktorgradsavhandling, 2011-12-08)
      This thesis investigates the structure and function of planktonic food webs at two sites between Greenland and the Svalbard Archipelago, covering a coastal ecosystem influenced by Atlantic water masses (Kongsfjorden, 78º N) and a more oceanic system off the East Greenlandic shelf, influenced by the outflow of Arctic water and sea ice from the Arctic Ocean (northwest Fram Strait, 75 - 80º N). In ...

    • Fishing for Advice : the case of the Norwegian Reference Fleet 

      Bjørkan, Maiken (Doctoral thesis; Doktorgradsavhandling, 2011-12-15)
      This dissertation is about the changing relationship between science and society and the attempt to organize knowledge production and advisory processes in new ways: How can the relations between science and society be organized in a way that ensures sound advice as well as democratic ideals such as transparency and inclusion? Is it possible to relax the boundary between science and society without ...

    • Studies on the amphipod genus Metopa (Stenothoidae) : Taxonomy, Ecology, Phylogeny 

      Tandberg, Anne Helene S. (Doctoral thesis; Doktorgradsavhandling, 2011-12-19)
      The Amphipod-genus Metopa is a relatively large genus, with currently 55 accepted species. This PhD thesis consists of redescriptions of 23 of these species based on typespecimens or specimens collected and identified by the original authors; this has been done to create consistent descriptions that could form a basis for a phylogenetic analysis of Metopa. For some species Scanning Electron ...

    • Key genes and regulators associated with sexual differentiation and gonad development in Atlantic cod (Gadus morhua L.) 

      Johnsen, Hanne (Doctoral thesis; Doktorgradsavhandling, 2012-02-17)
      Atlantic cod (Gadus morhua L.) is a promising cold-water aquaculture species, but early sexual maturation is a major problem in today’s cod farming. Teleosts display a wide variety of sex determination and sex differentiation mechanisms, ranging from genetic to environmental factors and the sexual plasticity in gonads and brain possibly reflects on a combination of these. From a practical point of ...

    • Plant regulatory networks : RNA binding proteins as mediators of communication between DNA containing compartments by dual targeting 

      Fuss, Janina (Doctoral thesis; Doktorgradsavhandling, 2012-05-11)
      The endosymbiosis-derived organelles within a plant cell, plastids and mitochondria, have to be equipped with a certain set of proteins to be fully functional. This set of proteins is encoded by different genomes: the organellar genomes and the nuclear genomes. This setup poses some interesting challenges for the regulation of gene expression and protein transport. On the one hand, the targeting ...

    • Characterization of a Cytokinin Response Factor in Arabidopsis thaliana 

      Ketelsen, Bernd (Doctoral thesis; Doktorgradsavhandling, 2012-05-15)
      Acclimation responses to environmental growth conditions in plants involve complex and fine-tuned signalling networks. Environmental signals, biotic and abiotic, are received and mediated, and lead eventually to transcriptional regulation. The plant hormones are vastly involved in these processes as intercellular mediators whereas the reception of such a hormone at the site of action involves ...

    • Calanus glacialis : the role of lipids in the life cycle and for the Arctic pelagic food web 

      Wold, Anette (Doctoral thesis; Doktorgradsavhandling, 2012-05-23)
      The Arctic marine ecosystem is characterized by strong seasonality and a short but productive period of primary production in the spring when the ice breaks up. Calanus glacialis is one of the key links between primary producers and higher trophic levels, and it is adapted to the strong seasonality by life cycle traits such as; seasonal vertical migration, diapausing, reproduction in the spring and ...

    • Technology transfer and R&D policy in a knowledge-based society 

      Michalsen, Anita (Doctoral thesis; Doktorgradsavhandling, 2012-06-01)
      Abstract My thesis focuses on technology transfer and innovation policy in a knowledge-based society. In particular, I analyse the firms’ incentives to invest in research and development (R&D), the transfer of technological knowledge to a rival and government stimulation of R&D investment. Further, I analyse the incentives to engage in R&D cooperation in different market structures. By coordinating ...

    • PLGA and PLA particles as vaccine delivery systems for Atlantic salmon : a study on formulation and use with an emphasis on immune responses 

      Fredriksen, Børge Nilsen (Doctoral thesis; Doktorgradsavhandling, 2012-06-07)
      Vaccines are regarded as the safest and most cost-effective strategy to prevent infectious diseases. For some diseases, vaccine improvements are required as protection levels are still inadequate. The key to solving this challenge might lie in the development of more efficacious vaccine delivery systems and adjuvants. Poly (lactide-co-glycolide) (PLGA) is a biodegradable polymer which has an extensive ...

    • Management of the alien invasive red king crab Integrating natural and social science perspectives 

      Falk-Petersen, Jannike (Doctoral thesis; Doktorgradsavhandling, 2012-06-12)
      The red king crab (Paralithodes camtschaticus) is a highly valuable resource that also represents a potential threat since it is an alien invasive species in the Barents Sea ecosystem. This thesis explores the use of different interdisciplinary frameworks to analyse how ecological, social and economic concerns could be accounted for in deciding on how the king crab should be managed in the Norwegian ...

    • The governance of Sami reindeer husbandry in Norway : institutional challenges of co-management 

      Ulvevadet, Birgitte (Doctoral thesis; Doktorgradsavhandling, 2012-06-15)
      Denne avhandlingen er basert på en kvalitativ studie fra forvaltningen av reindriften i Norge. Målet med forvaltningen av reindriften i Norge er å oppnå en økologisk, økonomisk, og kulturell bærekraftig reindrift. Disse målene har blitt forsøkt oppnådd gjennom et governance system fordi myndighetene har erkjent at det å inkludere ressursbrukere i forvaltningsmessige beslutningsprosesser skaper en ...